Bill Dudleston is one of the few (very few) audio engineers (he is a graduate from University Illinois @ Urbana-Champaign), who understands the significance of controlled directivity. He brought that years ago (early 90's) with the Whisper. Once you hear the Whisper (and I assume the Helix), all the other speakers he has built sound broken. What he hasn't done is bring that technology down into the less than $10K range. Others have, however, they have used different design principles such as waveguides and horns.
When I listened to the Whispers they were indeed amazing. They definitely need the Steradian processor as the (4) 15 inch woofers are in a push pull open baffle array. In other words, the bass ski slopes from 100 hz on down and it needs boost which is what the Steradian provides. The bass was incredibly clean. Still, when he added additional powered subwoofers, the system sounded much better. At that point you were talking about $20K (used prices).
I used to own the Studios in college and loved them at the time. I had listened to the entire line in Springfield from the Classics to the Whispers, however the Whispers just stood out and always sounded live, no doubt, due to the controlled directivity.